Went on a cruise today with a friend who swapped a 2jz with a T67 bb turbo, sard 800 injectors into a jza70, all this is managed by a 2jz mines ecu and emanage ultimate. For some reason the car won't kick start when it is hot, but will start if given a push. So far they are thinking that it is a safety feature on the emu which is causing that. My question is had anyone had such a problem? Car starts fine when cold.
Wednesday, May 11, 2011 - 12:38 pm, by: Sykes Ettinoffe(Sikes)
Really not sure. The start motor cranks the engine even while on a charger. He ran test on the injectors and he believes that they are not receiving a pulse. Just wondering if a test lamp or probe would be sufficient to test for a signal lasting milliseconds. Also think the fuel pump ecu has been bypassed a while now. This is car has gone through a few engine combos but this was the first time the harness has been hacked. Would leaky capacitor in the mines ecu contribute to such a problem?
Friday, May 20, 2011 - 07:21 am, by: Cihan Aday(Cihan)
Its not the Emanage..
Overall injector trim is too high.
That means there isn't enough prime pule or post start enrichment to first start and then run the engine at temperature.
This happens because the high impedance 800cc SARD injectors operate on a big 'lag' time.
If the ECU output pulse width isn't long enough, the injectors don't turn on. You will find that in some cases, the engine is either rich, or its too lean - just by moving one or two injection percentage points.
The symptoms will be similar with a standalone ECU. The difference is, there is more control over how the lag is managed.
Low impedance 'peak & hold' injectors are preferred for larger applications (over 500cc per injector).
Why does Toyota use high impedance 'saturated' type injectors? Most likely because they run cooler and are more reliable by design. Generally , under 500cc the lag isn't large enough to impact tuning or the engines operation.
Also you will find if you get the hot starts spot on, you will be running excessively rich when cold.
The standard ECU adds an additional (set) pulse width when cold, which with big injectors means alot more fuel. If this is trimmed out, then your left lean when hot.
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